Thread-controlling mechanism for sewing machines



Oct. 14, 1947.4

- THREAD-CONTROLLING MECHANISM FOR SEWING MACHINES R. BECKER Filed March 5, 1946 4 Sheets-Sheef 1 3ra/vorm A www,

R. BECKER 2,428,956 THRAD-jCONTROLLI'NG MECHANISM FOR SEWING MACHINES ocr; 14, 1947.

Filed Marh 5. 1946 4 Sheets-Sheet 2 R. BECKER oct. 14,1947.

'THREAD-CONTROLLING MECHANISM FOR SEWING MACHINES Filed March 5;, 1946 4 Sheets-Sheet 3 Oct. 14, 1947. V R. lsEcKl-:R 2,428,956

THREAD-CONTROLLING MECHANISM FOR SEWING MACHINES Filed March 5, 1946 4 sheets-sheet 4 f GMM,

Patented Oct. 14, 1947 2,42e 3,f95o.V THREAD--ooNTnonLINGgMEoHANIsM-Fon- SEWING; MACHINES Eggink-.Becken North Planfeld,. N, Jf., assignon ngenManufaturngompany, Elizar htlihvN, LA.I jan corporation of New Jersey Application-March; 1946, SeriatltNm 65250.81?.

11.A Claims... i C1-mgm invention. relates. to; chain-stitch; sewing'. ma 'nes-. nini;d more. nartfic I asrlyl to; a; thread. cont11i-151g;v mechanism. ionA a thread-carrying; loopen hov i:r1:g.:.lohnseizing.l and". sheddine:. mover: ment inventonihnswior: am Qbj'eotgftoprovide. a.

Simplied and emeientnieohonism .for1oQntroi1ing the.. thread Supplied :to the: iooper, of f a.; chain- Stitch..sevtii-11g.rrietzdhine,4 with. a degree. ofninetyv sliQh: aigto; p enmiji; operation oirtzhe machine at: highspeedeend-to prevent; snarling'.- whipping. andv` knot-ting-nf the longer-thread during such opera; tion@ AllhflfgbieGtifofthefirniention isto provide an imnroyed; thread-con roller; whionis.. timed;v to dro-Wi thread. fromz the; supplyaandsubsequently to.k assist in controllinggfthe; Mopar-thread tothe t.l nt-the;..1=mb: of he. looperfthread-'loop y 1s, seiz d bythei, pigeaden asfthe same is. atua ed;` to open the usuakthread-triangle, sg. htl i vthesnreader until theneedleon its-next@ voor gpenetratnstroke.hasntered vthe thread-- trie-nele..

Witzhf the. above-.1 enfin-Other Objects in View, as will; hereinafter appear; thenvention comprises. the devicesn combinations; andzigarjrangementsn of piet-rtsi herenztfterg s et forth.. and. illustrated; the @.Qompenving .drawings of-.fai preferred-.- ein-Y lootinnentV ,ofgftlie invexi-tifon,A from which; the..sev. elialrfeatllesof; theinnention andthe. advantages attained thereby will ;b e-.rea d1y.- .understoud by? those. skilledf in,the zart;

Fie- 1 is a liront elevation, .mf-rtw section.. or: the. head1-end 0 2;Cha, e.sti;teh Sewing.. maehine. embodying the present invention.;

Fig 211sa left hnndtend, elevationatviewQi the. Sewing -maehinwwifhthe; bedeprtion in Sectionn showing thepathf of-trnvelof the leonor-thread.

.-Fiefi .represents ae-fenlfreei1- transverseverbi: t' 1 viewalsen wbstantiafllyot theline;

Orb-fe dLIW' .;K mov-.ement of. #0116;-fthreadroontrouine..eye inthe, Montt-:Shanks Reierrine more -psrtioulsrilyiftofthedrawings thsfiinveritlien: is disclosed embodied jin a sew: ing rrachine having a fn Qnipiising 7a. box-.- likezb ed. :.Ii tfromioneoendpf. .tuch :risesthe .usual standordfnqt .shown9.--i of an otethangtnehrodete.

" arm-shaft I3.

n eteei tQ- -thef need1 e=bars I5 by npairoff:links..` 211g Seolwlred,tothe1 lower-,end ofi each. of needle-bttrsii Hivl a 4: lolook.. 21,-- havingy extending thenethrugh tvvnl horizontally disposed l.rods 272.-t uponwhich areecured for lateral `ndjilstjfri'ieerift at, plurality ofzjnveedle-olamps; 2 31v Each ofthe;v ne'edle-olafm-pvs-ZS; -carries --an* .eyevpointedi threads. Cntryingnntedlefr. Themed-lesione adapted-:- to.-Y penetrate workY W. whichA isv heldY uponr the; usual'thioat-platei 5 of-fthe/bod l 9v by Ithe pressen. feet i 2 6 cotrried. onqtlfiel regulan spring depressedl pressen-bars.ZIendwise slidable in the Inaolflnfe; head l2.

Thevvorl` WY s.-,adapte d1t0bef fed-'past they moed-lessi@ by I an-yy'suitab'lef-feeding. mechanismV irimudirigfr a@ serrated`v feedfdog- 28 operable. through conventi-cual feed-dogfslots 29- formed..

1.the-thro awtg-vpla.-

Thesconzieotionsl illus-- tratedwn-the fdliawlngs for imparting; i Work-.adv Y vancingg; movements. to-v the vfeed-dog 2S vetre the;y same as thosedisclosedi fn.A :my U.; S. Patent No.- 2;1Q9,'- 242; dated--0ct- ,15jA 1946; and, therefore, no; furtherjroferene thereto is-deemed necessaryin. thstase y Cooperatingewith-eaohmeedle 2 4; inthe forma-- 'Thus rotation of the bed-shaft The looper-carrier 35 is adjustably secured to the proximate ends of aligned looper-driving shafts 31 and 38; the looper-carrier and the aligned looper-driving shafts forming, in eiect, a single composite looper-carrying and -actuating shaft. In order that the composite looper shaft 35, 31 and 38 may be operated smoothlyA and without anybnding or cramping action, means is provided for actuating the shaft synchronously from each end thereof. Accordingly, the looper shaft sections 31 and 38 are journaled, respectively, in eccentrically located bores 39 and 40 formed in sleeves 4| and 42 carrying eccentric gears 43 and 44, The sleeves 4| and 42 are journaled in bearing bushings 45 and46 in the base Hl of the machine.

Secured eccentrically upon the bed-Shaft I4 (Fig. 3) are two looper-driving gears 41 and 48 complemental to and meshing, respectively, with the gears 43 and 44 on the sleeves 4| and 42. |4 effects, through the eccentric gears 43-41- and 411-48, rotation at a varying rate of the sleeves 4| and 42 in their bearing bushings 45 and 46, thereby moving the looper-carrier 35 laterally of its axis in an orbit.

During the variable speed travel of the loopercarrier 35 in its orbit, said looper-carrier is also oscillated on its own axis. This oscillation is effected by the mechanism clearly shown in Fig. 4, and comprises preferably an eccentric or crank 49 formed on the bed-shaft I4. The crank 49 is embraced by a split-block 50 having in its lower portion a cylindrical bore 5|. Slidably tted within the bore 5| is a lever-pin 52 having a ;split head 53 secured by screws 54 and 55 upon i ithe portion 38 of the looper-actuating shaft. j From the above description, it will be understood 'that the looper-carrier 35 is caused to move in :an orbital path by the lrotation of the aligned isleeves 4| and 42 and that simultaneously with :this movement the looper-carrier is caused to foscillate about the axis of the aligned shaft sections 31 and 38 by the pin-and-sleevc connection :5i-52.V The path traversed by the looper 3U resulting from this compound movement of the looper-carrier 35 is fully disclosed in my above .mentioned U. S. patent application Serial No. 631,302.

As is common in chain-stitch machines, each looper 3|! has cooperating therewith, in forming the usual thread-triangle for entrance by the Idescending needle, a spreader-finger 56. These :spreader-ringers are secured to a horizontally disposed member 51 mounted to slide in a channel 58 provided in the under side of the throat-plate S25. At one end the member 51 is connected to a :slide-bar 59 (Fig. 1) slidingly mounted within a guide-way 60 formedin the under side of a 'block 6| secured to the bed I0 of the machine. The slide-bar 59 carries a roller-stud 62 which tracks a cam-groove'63 formed in a barrel-cam 64 suitably secured to a -side face of the gear 43.

It will be observed in Fig. 2 that the spreaderringer 56 is adapted to seize the limb of the looperthread L leading from the eye in the looper-beak 32 to the last stitch in the work. After this thread-limb is seized, the spreaderfflnger 56 continues in its movement to distend said threadlimb, thereby eiectively to enlarge and properly position the thread triangle, of which the seized thread-limb is a part, for entrance by the descending needle 24. In order to insure the seizure of the thread-limb by the spreader-finger 56, it is necessary to control the looper-thread to the ex- 4 tent that the thread leading from the eye in the looper-beak 32 to the work is substantially straight and intersects the path of travel of the spreader-finger. Moreover, after seizure of the looper-thread by the spreader-finger, it is essential that the looper-thread be controlled so that the vseized thread-limb be retained on the spreader-finger at least` untilv the needle has entered the formed thread-triangle.

Novel means is provided for drawing a length of thread from the supply and for obtaining the above described thread control. This means is best illustrated in Figs. 2 and 5. It will be seen that the cylindrical shank 33 of the looper 30 has lli` adjacent its lower end is formed with a transverse been extended below the looper-carrier 30, and

thread-eye 65 which moves relative to and cooperates with fixed thread-guides 66 and B1. The thread-guide 66 is formed in an angle-bar 68 which is slotted, as at 69, to receive clamp-screws 18, whereby the angle-bar 68 can be vertically adjusted for a limited extent. The thread-guide 61 is formed in an angle-bar 1| secured by screws 12 to the bed I0. It will be appreciated that the movable thread-eye 65 is disposed on that side of the axis of movement of the carrier 35 opposite or remote from the looper-blade 3| and that thev thread-eye will move in an orbital path somewhat like that of the looper-beak 32, but in the opposite direction. The exact path of movement of the thread-eye 65 during the stitch-forming cycle is designated as O in Fig. 5. The most desirable control of the looper-thread L is obtained by locating the xed thread-guides 66 and 61 on opposite sides of the movable thread-eye 65, so that the thread-eye operates on the thread passing between the thread-guides. Also. it is desirable to locate the fixed thread-guides 66 and 61 reasonably close together so that the length of thread extending from the thread-guide 61 through the thread-eye 65 and to the threadguide 66 will be short. This renders the action of the movable thread-engaging element or threadeye 65 more accurate in its effect on the thread by minimizing stretching resulting from the inherent elasticity in the thread. It will also be seen that the orbital path of movement of the thread-eye 65 is located at one side of a straight line connecting the two thread-guides 68 and 61.

Having thus set forth the nature of the invention what I claim herein is:

l. A sewing machine having in combination, a reciprocatory tliread-carryingY needle, a threadcarrying chain-stitch vlooper complementa] to said needle in the formation of stitches, a carrier for said looper, means for moving said carrier about an axis to impart loop-seizing and loop-shedding movements to said looper, a pair of thread-guides, and a thread-engaging element carried by said carrier at one side of the axis of movement of said carrier and operable on the thread passing between said thread-guides.

2. A sewing machine having in combination, a reciprocatory needle, Va thread-carrying chainstitch looper complemental to said needle in the formation of stitches, alcarrier movable about an axis and supporting said looper at one side of said axis, means for actuating said carrier, a pair of thread-guides for directing the looper thread, and a thread-engaging element carried by said carrier on the side of the carrier-'axis opposite to said looper for contacting the thread passing between said thread-guides.

y 3. A sewing machine'having in combination, va reciprocatory needle, a thread-carrying chainstitch looper having an eye-pointed beak complemental to said needle in the formation of stitches, a carrier supporting said looper, means for'aotuating said carrier about an axis in a manner to move said looper-beak in an orbital path, a pair of thread-guides for said looper-thread, and a thread-engaging element operable on the thread passing between said thread-guides, said threadengaging element also traversing an orbital path and movable in a direction opposite to that of the looper-beak.

4. A sewing machine having in combination, a reciprocatory needle, a thread-carrying chainstitch looper having a beak complemental to said needle in the formation of stitches, a carrier supporting said looper and movable in an orbital path about an axis, means for moving said carrier, a pair of xed thread-guides for said looper-thread, and a thread-engaging element carried by said carrier and spaced from the axis about which said carrier moves, whereby said thread-engaging element traverses an orbit between said xed thread-guides.

5. A sewing machine having in combination, a reciprocatori7 needle, a thread-carrying chainstitch looper having a beak complemental to said needle in the formation of stitches, a pair of thread-guides, a carrier supporting said looper and movable in an orbital path about an axis disposed transversely of the plane containing said iixed thread-guides, and a thread-engaging element supported by said carrier and disposed to traverse an orbital path between said threadguides.

6. A sewing machine having in combination, a reciprocatory needle, a thread-carrying chainstitch looper having a beak complemental to said needle in the formation of stitches, a carrier supporting said looper and movable in an orbital path s about an axis, means for moving said carrier, a

pair of i-lxed thread-guides for said looper thread, and a thread-engaging element carried by said carrier and disposed so that said element moves in an orbital path to one side of a straight line connecting said thread guides.

'7. A sewing machine having in combination, a reciprocatory needle, a thread-carrying chainstitoh looper, a carrier supporting said looper and movable about an axis, means for actuating said carrier about said axis so that said looper moves in an orbit contained in a plane parallel to said needle,'a pair of spaced thread-guides for directing said looper-thread, a movable thread-engaging element disposed to operate on the looperthread between said thread-guides, and means to move said thread-engaging element in an Orbit similar to the orbit oi movement of said looper.

S. A sewing machine having in combination, a reciprocatory thread-carrying needle, a threadcarrying chain-stitch looper complemental to said needle in the formation oi stitches, a carrier for said looper, mea-ns for moving said carrier about an axis to impart loop-seizing and loop-shedding movements to said looper, and a thread-controller for said looper-thread including spaced threadguides, and a thread-eye carried by said looper and operable o-n the thread passing between said thread-guides.

9. A sewing machine having in combination, a reciprocatory thread-carrying needle, a threadcarrying chain-stitch looper having a blade terminating in a loop-seizing beak, a carrier movable about an axis and supporting said looper so that its loop-seizing beak is at one side of said axis, means for actuating said carrier, and a threadcontroller for said looper-thread including spaced thread-guides, and a thread-eye provided in said looper on that side of the carrier-axis remote from the looper-beak.

l0. A sewing machine having in combination, a reciprocatory thread-carrying needle, a threaded chain-stitch looper having a loop-seizing beak and a supporting shank, a carrier movable about an axis, means for securing said looper-shank to said carrier, and a thread-controller for said looper-thread -including spaced xed threadguides, and a thread-eye formed in said loopershank and operable on the thread between said thread-guides.

11. In a chain-stitch sewing machine, in combination, a reciprocatory thread-carrying needle, a thread-carrying looper complemental to said needle in the formation of stitches, means including a pair of spaced thread guides for directing the looper-thread to said looper, a lo-oper-thread controller in engagement with the portion of the looper thread extending from one to the other of said thread-guides, and actuating means oper- Vatively connected for rocking said controller about an axis having an orbital path of movement.

RUDOLPH BECKER.

REFERENCES CITED UNITED STATES PATENTS Name Date Moffatt Oct. 30, 1928 Number 

